Commercial dough production often involves production of large quantities of individual dough portions Weight monitoring of dough portions has been carried out by checkweighing systems, such as weigh belts and weigh belt feeder systems. These apparatus, however are only capable of determining a projection of the actual static weight by collecting samples of output from a weight sensor as individual dough portions, as well as the section of the conveyor belt supporting the portion, pass over the sensor. Also, as the weight samples are collected, the data accuracy can be degraded by the effects of air currents, vibration from surrounding equipment, vibrations or harmonics generated by the dough portion's movement on the conveyor and other physical forces on the sensor.
Also, since it is necessary to use a weighing device with sufficient capacity to support the weight of the empty conveyor along with the weight of the dough portion to be weighed, larger capacity weight sensors must be used, which are much less sensitive than smaller weighing sensors of the same variety.
Additionally, due to the physical properties of extruded dough portions, they tend to adhere to any surface they contact. To limit the amount of adhesion, it is common for flour to be sifted onto the devices transporting dough portions. In prolonged operation, flour may randomly accumulate in various locations along the transport mechanism, including in the area where weight measurements are taken, thus introducing errors in the weight indications.
Further, due to the semi-solid nature of raw dough, transporting dough portions by a belt conveyor requires that the plane of the initial conveyor belt be at a higher elevation than subsequent downstream conveyor belts, to eliminate the possibility of dough portion being forced downward through the transition between consecutive sets of conveyor rollers. Also, in a system employing an in-motion belt weighing mechanism, the abrupt transition of the dough portion from an upstream conveyor to the weighing conveyor can impart an impact or torsion force to the weight sensor, resulting in inaccuracies in the measured weight.
Additionally, there are physical constraints with in-motion weighing systems, including that the weighing conveyor must be of substantial length, generally at least thirty inches, which may create problems in integrating the weighing system with existing equipment.
Another commonly used means of weighing divided dough portions involves the use of a static weigh scale, whereby an operator may randomly remove and weigh dough portions and perform a statistical calculation to determine if portion weights are acceptable. This method also has several disadvantages, including that substantial variations in individual portions may remain undetected and that removal of sample portions from the processing sequence may affect production efficiency.